tcp: Remove unnecessary arg from tcp_enter_cwr and tcp_init_cwnd_reduction

Since Yuchung's 9b44190dc11 (tcp: refactor F-RTO), tcp_enter_cwr is always
called with set_ssthresh = 1. Thus, we can remove this argument from
tcp_enter_cwr. Further, as we remove this one, tcp_init_cwnd_reduction
is then always called with set_ssthresh = true, and so we can get rid of
this argument as well.

Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index c9a75db..0aeb2eb 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -928,7 +928,7 @@ static inline __u32 tcp_current_ssthresh(const struct sock *sk)
 /* Use define here intentionally to get WARN_ON location shown at the caller */
 #define tcp_verify_left_out(tp)        WARN_ON(tcp_left_out(tp) > tp->packets_out)
 
-void tcp_enter_cwr(struct sock *sk, const int set_ssthresh);
+void tcp_enter_cwr(struct sock *sk);
 __u32 tcp_init_cwnd(const struct tcp_sock *tp, const struct dst_entry *dst);
 
 /* The maximum number of MSS of available cwnd for which TSO defers

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index bb68496..2e16afb 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -2475,7 +2475,7 @@ static bool tcp_try_undo_loss(struct sock *sk, bool frto_undo)
  *     losses and/or application stalls), do not perform any further cwnd
  *     reductions, but instead slow start up to ssthresh.
  */
-static void tcp_init_cwnd_reduction(struct sock *sk, const bool set_ssthresh)
+static void tcp_init_cwnd_reduction(struct sock *sk)
 {
        struct tcp_sock *tp = tcp_sk(sk);
 
@@ -2485,8 +2485,7 @@ static void tcp_init_cwnd_reduction(struct sock *sk, const bool set_ssthresh)
        tp->prior_cwnd = tp->snd_cwnd;
        tp->prr_delivered = 0;
        tp->prr_out = 0;
-       if (set_ssthresh)
-               tp->snd_ssthresh = inet_csk(sk)->icsk_ca_ops->ssthresh(sk);
+       tp->snd_ssthresh = inet_csk(sk)->icsk_ca_ops->ssthresh(sk);
        TCP_ECN_queue_cwr(tp);
 }
 
@@ -2528,14 +2527,14 @@ static inline void tcp_end_cwnd_reduction(struct sock *sk)
 }
 
 /* Enter CWR state. Disable cwnd undo since congestion is proven with ECN */
-void tcp_enter_cwr(struct sock *sk, const int set_ssthresh)
+void tcp_enter_cwr(struct sock *sk)
 {
        struct tcp_sock *tp = tcp_sk(sk);
 
        tp->prior_ssthresh = 0;
        if (inet_csk(sk)->icsk_ca_state < TCP_CA_CWR) {
                tp->undo_marker = 0;
-               tcp_init_cwnd_reduction(sk, set_ssthresh);
+               tcp_init_cwnd_reduction(sk);
                tcp_set_ca_state(sk, TCP_CA_CWR);
        }
 }
@@ -2564,7 +2563,7 @@ static void tcp_try_to_open(struct sock *sk, int flag, const int prior_unsacked)
                tp->retrans_stamp = 0;
 
        if (flag & FLAG_ECE)
-               tcp_enter_cwr(sk, 1);
+               tcp_enter_cwr(sk);
 
        if (inet_csk(sk)->icsk_ca_state != TCP_CA_CWR) {
                tcp_try_keep_open(sk);
@@ -2670,7 +2669,7 @@ static void tcp_enter_recovery(struct sock *sk, bool ece_ack)
        if (inet_csk(sk)->icsk_ca_state < TCP_CA_CWR) {
                if (!ece_ack)
                        tp->prior_ssthresh = tcp_current_ssthresh(sk);
-               tcp_init_cwnd_reduction(sk, true);
+               tcp_init_cwnd_reduction(sk);
        }
        tcp_set_ca_state(sk, TCP_CA_Recovery);
 }
@@ -3346,7 +3345,7 @@ static void tcp_process_tlp_ack(struct sock *sk, u32 ack, int flag)
                tp->tlp_high_seq = 0;
                /* Don't reduce cwnd if DSACK arrives for TLP retrans. */
                if (!(flag & FLAG_DSACKING_ACK)) {
-                       tcp_init_cwnd_reduction(sk, true);
+                       tcp_init_cwnd_reduction(sk);
                        tcp_set_ca_state(sk, TCP_CA_CWR);
                        tcp_end_cwnd_reduction(sk);
                        tcp_try_keep_open(sk);

diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index bcee13c..306dd5d 100644 (file)
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -979,7 +979,7 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
        if (likely(err <= 0))
                return err;
 
-       tcp_enter_cwr(sk, 1);
+       tcp_enter_cwr(sk);
 
        return net_xmit_eval(err);
 }